Evening capital. (Annapolis, Md.) 1884-1910, 1887-03-15
ANNAPOLIS, MD. TUESDAY EVENING, MARCH Is, 1887
-lne fAlIn0spnero Ol caves.


atmosphere with which we are acquaint-
ed is found in Mammoth Cave. Ky.
This cave, or rather system of caves,
is very extensive, greatly exceeding
the other two notable caverns in our
country-the Luray of Virginia and
the Wyandott of Southern Indiana.
The passageways of Mammoth Cave
have combined length of over $50
miles, and their area covers hundreds
of acres. tits estimated that the entire
volume of atmosphere thus inclosed ex-
ceeds twelve million cubic yards. In,
this underground world the ordinary
atmospheric changes are unknown,
summer and winter arc unknown, and
the heat of the sun never reaches its
unbroken night.
Like all our larger caverns, the tenn
perature is alike at all times and sea-
sons. In the summer there is brisk
outward current, having temperature
of $50 to 54o. This current is doubt
less fed by certain leakages of air which
filter through the sinkholes, which dis
charge their moisture at certain points
in the cave system.
In the winter, there is current Of
air setting outward. This is not per-
ceived at a distance of one-fourth of q
mile from the entrance. 1t neverthe-
less depresses the thermometer few
degrees, and its effect upon the humid
ity of the air is evident at the distance
of three-fourths of mile.
For the first time hygrometric obser-
vations have been carefully made as to
this unique body of atmosphere. The
dryness of the air has often been not
ticed, and the resultant inter beds were
esteemed matter of national impor-
tance during the war of 1912. :
In the Gothic Gallery" several
miles underground, visitors have been
wont to deposit their cards, and these
cards have remained for years, fresh
as new, save where moist finger prints
have left behind them the germs of
mould. The ground is seemingly dusty,
but-still the dust, if stirred, will not
rise in the air, nor soil polished shoe.
In these portions of the cave, which
seemed destitute of moisture, the wet
and dry bulbs of the hygrometer
showed the same figure, the variations
seldom exceeding one-fourth to one
half of degree. The humidity rang
ed between SO and saturation. With
the thermometer at 54o, the wet bulb
would range between 534o and sac,
and the dew point would be between
53 1-10o and 80 7-109. The singular
fact was noted that the same tempera-
k,,,. lo1 ~ he rf he.
floor of the cave; and where differences
of 200 to 800 feet elevation occurred,
the thermometer would be depressed
one or two degrees at the higher as
compared with the lower altitude. The
humidity would, however. remain a
constant quantity. This can be ac-
counted for only on the supposition
that the supply of air, slowly admitted
from above, is chilled by the absorption
of moisture during the first stages of
its descent, and becomes slowly warm
ed before completing its full descent of
800 feet Mould is rarely seen in the
cave, but wherever it occurs, snowy
whiteness and luxuriance of growth are
noted.
One avenue of the cave is devoted.
with excellent success, to the growth
of mushrooms, and no doubt such an
| atmosphere might have an industrial
value for other purposes.
Several consumptives once tried to
live, and get well, in the cave. But
the result was disastrous. The lack of
light was, no doubt, one reason of
this; but the hygromctric condition Of
the air, Of which nothing was then
known, by greatly retarding healthy
perspiration, doubtless hastened the
fatal result.-R. Norton, IN Scientific
american.